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The Interferometric Monitor for Greenhouse Gases (IMG) operated aboard the polar-orbiting Advanced Earth Observing Satellite from October 1996 through June 1997. The IMG measured upwelling infrared radiance at fine spectral resolution. This paper identifies previously undocumented issues with IMG interferograms and describes procedures for correcting the majority of the affected data. In particular, single-sided interferograms should be used to avoid large noise bursts, and phase ambiguities must be resolved in uncalibrated spectra before radiometric calibration. The corrections are essential for studies that require accurately calibrated radiance spectra, including those that track atmospheric changes globally on decadal time scales. [c] 2010 Optical Society of America OCIS codes: 300.6300, 120.3180, 280.4991, 290.6815, 120.6085.

Trade-off studies on spectral coverage, signal-to-noise ratio (SNR), and spectral resolution for a hyperspectral infrared (IR) sounder on a geostationary satellite are summarized. The data density method is applied for the vertical resolution analysis, and the rms error between true and retrieved profiles is used to represent the retrieval accuracy. The effects of spectral coverage, SNR, and spectral resolution on vertical resolution and retrieval accuracy are investigated. The advantages of IR and microwave sounder synergy are also demonstrated. When focusing on instrument performance and data processing, the results from this study show that the preferred spectral coverage combines long-wave infrared (LWIR) with the shorter middle-wave IR (SMidW). Using the appropriate spectral coverage, a hyperspectral IR sounder with appropriate SNR can achieve the required science performance (1 km vertical resolution, 1 K temperature, and 10% relative humidity retrieval accuracy). The synergy of microwave and IR sounders can improve the vertical resolution and retrieval accuracy compared to either instrument alone. OCIS codes: 010.0010, 010.1280, 120.0280, 120.6200.

Mucosal eosinophils increase in a number of gastrointestinal diseases that are often associated with altered epithelial barrier function, including food allergic enteropathies and inflammatory bowel diseases. Although eosinophils are known to secrete biologically active mediators including granule proteins, their role in gastrointestinal diseases is uncertain. The aim of this study was to determine the impact of eosinophils on intestinal barrier function. Epithelial barrier function was determined in a coculture of eosinophils and T84 epithelial cells and in a routine model of T helper (Th) type 2-mediated colitis. Coculture conditions resulted in decreased transepithelial resistance (TER) and increased transepithelial flux. Cell-free coculture supematants contained a [greater than or equal to]5-kDa soluble factor that also diminished TER; these supernatants contained the eosinophil-granule proteins major basic protein (MBP) and eosinophil-derived neurotoxin (EDN). T84 barrier function decreased significantly when basolateral surfaces were exposed to native human MBP but not EDN. Additional studies identified downregulation of the tight junctional molecule occludin as at least one mechanism for MBP action. MBP-null mice were protected from inflammation associated with oxazolone colitis compared with wild-type mice. In conclusion, MBP decreases epithelial barrier function and in this manner contributes to the pathogenesis of inflammatory bowel diseases. tight junction; eosinophilic gastroenteritis; food allergy

The theoretical basis is explored for inferring the microphysical properties of ice clouds from high spectral resolution infrared (IR) observations. Extensive radiative transfer simulations are carried out to address relevant issues. The single-scattering properties of individual ice crystals are computed from state-of-the-art light scattering computational methods and are subsequently averaged for 30 in situ particle size distributions and for four additional analytical Gamma size distributions. The nonsphericity of ice crystals is shown to have a significant impact on the radiative signatures in the IR spectrum. Furthermore, the errors associated with the use of the Henyey-Greenstein phase function can be larger than 1 K in terms of brightness temperature for large particle effective sizes (~ 80 [micro]m) at wavenumbers where the scattering of the IR radiation by ice crystals is not negligible. The simulations undertaken in this paper show that the slope of the IR brightness temperature spectrum between 790-960 [cm.sup.-1] is sensitive to the effective particle size. Furthermore, a strong sensitivity of the IR brightness temperature to cloud optical thickness is noted within the 1050-1250-[cm.sup.-1] region. Based on these spectral features, a technique is presented for the simultaneous retrieval of the visible optical thickness and effective particle size from high spectral resolution IR data for ice clouds. An error analysis shows that the uncertainties of the retrieved optical thickness and effective particle size have a small range of variation. The error for retrieving particle size in conjunction with an uncertainty of 5 K in cloud temperature, or a surface temperature uncertainty of 2.5 K, is less than 15%. The corresponding errors in the uncertainty of optical thickness are within 5% to 20%, depending on the value of cloud optical thickness. The applicability of the present retrieval technique is demonstrated using airborne high-resolution IR measurements obtained during two field campaigns. Index Terms--Ice Clouds, infrared spectrum, retrieval.

The Moderate Resolution Imaging Spectroradiometer (MODIS) is one of five instruments aboard the Terra Earth Observing System (EOS) platform launched in December 1999. After achieving final orbit, MODIS began earth observations in late February 2000 and has been acquiring data since that time. The instrument is also being flown on the Aqua spacecraft, launched in May 2002. A comprehensive set of remote sensing algorithms for cloud detection and the retrieval of cloud physical and optical properties have been developed by members of the MODIS atmosphere science team. The archived products from these algorithms have applications in climate change studies, climate modeling, numerical weather prediction, as well as fundamental atmospheric research. In addition to an extensive cloud mask, products include cloud-top properties (temperature, pressure, effective emissivity), cloud thermodynamic phase, cloud optical and microphysical parameters (optical thickness, effective particle radius, water path), as well as derived statistics. We will describe the various algorithms being used for the remote sensing of cloud properties from MODIS data with an emphasis on the pixel-level retrievals (referred to as Level-2 products), with 1-km or 5-km spatial resolution at nadir. An example of each Level-2 cloud product from a common data granule (5 min of data) off the coast of South America will be discussed. Future efforts will also be mentioned. Relevant points related to the global gridded statistics products (Level-3) are highlighted though additional details are given in an accompanying paper in this issue. Index Terms--Clouds, meteorology, remote sensing, satellite applications, terrestrial atmosphere.

The Moderate Resolution Imaging Spectrora-diometer (MODIS) is an earth-viewing sensor that flies on the Earth Observing System Terra and Aqua satellites, launched in 1999 and 2002, respectively. MODIS scans a swath width of 2330 km that is sufficiently wide to provide nearly complete global coverage every two days from a polar-orbiting, sun-synchronous, platform at an altitude of 705 km. MODIS provides images in 36 spectral bands between 0.415 and 14.235 [micro]m with spatial resolutions of 250 m (two bands), 500 m (five bands), and 1000 m (29 bands). These bands have been carefully selected to enable advanced studies of land, ocean, and atmospheric properties. Twenty-six bands are used to derive atmospheric properties such as cloud mask, atmospheric profiles, aerosol properties, total precipitable water, and cloud properties. In this paper we describe each of these atmospheric data products, including characteristics of each of these products such as file size, spatial resolution used in producing the product, and data availability. Index Terms--Aerosols, Aqua, clouds, meteorology, remote sensing, satellite applications, Terra, terrestrial atmosphere, water vapor.

The Charcot-Leyden crystal (CLC) protein has been one of the most interesting subjects of biochemistry research due to its undetermined link with eosinophil functions. Diffraction data derived from a sample of CLC cyrstals, however, suggest that these proteins do not actually have affinity for beta-galactosides. Results further indicate that CLC proteins bind with mannose in a manner distinct with other galectin compounds.